CVE-2021-44020
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedAn unnecessary privilege vulnerability in Trend Micro Worry-Free Business Security 10.0 SP1 could allow a local attacker to escalate privileges on affected installations. Please note: an attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. This vulnerability is similar to but not identical to CVE-2021-44019 and 44021.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceA local privilege escalation vulnerability exists in Trend Micro Worry-Free Business Security 10.0 SP1 where the application grants unnecessary privileges to certain operations, allowing an attacker who already has low-privileged code execution to elevate to higher system privileges. This is a privilege of privilege vulnerability where the software assigns excessive permissions to users or processes.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 10.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Verify Trend Micro Worry-Free Business Security installation and versionCheck for the presence of the application and retrieve its version number. Common installation paths include C:\Program Files\Trend Micro\ or C:\Program Files (x86)\Trend Micro\. Look for executable files like 'Security Server' or related components, then right-click to view Properties for version information, or use the command: dir /s /b "C:\Program Files\Trend Micro\*" to list installed files.Affected if The installed version is exactly 10.0 (any SP1 variant)
-
Identify the Security Server service privilegesOpen Services (services.msc), locate the Trend Micro Security Server service (commonly 'Trend Micro Security Server' or 'TmListen'), right-click and select Properties. Check the 'Log on as' account and verify if the service runs under a highly privileged account such as LocalSystem or a domain administrator account.Affected if The service runs under an account with excessive system privileges beyond what is strictly required for its function
-
Examine file and folder permissions on the installation directoryRight-click the main Trend Micro installation folder, select Properties, then go to the Security tab. Review the permissions granted to users and groups. Check if low-privileged users or standard users have write or modify access to service executables, configuration files, or DLLs that are loaded by privileged processes.Affected if Standard or low-privileged users have write/modify permissions to files or folders accessed by privileged service components
-
Check for service executable path vulnerabilitiesOpen Registry Editor (regedit), navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services, locate the Trend Micro service entries. Examine the ImagePath value to verify if the executable path is properly quoted and does not contain spaces that could lead to path hijacking.Affected if The service executable path is unquoted and contains spaces, allowing potential DLL/search order hijacking by low-privileged users
-
Review application component permissionsExamine permissions on directories used by the security application for updates, logs, or temporary files. Check if the 'Users' group or 'Authenticated Users' group have write access to directories where the service loads or executes binaries.Affected if Non-admin users have write access to directories from which privileged services load executables or libraries
A system is affected if Trend Micro Worry-Free Business Security version 10.0 SP1 is installed AND the application or its services are configured with excessive privileges that permit low-privileged users to modify files or configurations accessed by higher-privileged processes.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply the vendor-supplied patch or update to Trend Micro Worry-Free Business Security 10.0 SP1 when available. Until then, limit local code execution privileges and monitor for suspicious privilege escalation attempts.
- Consultation4.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,152.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-44020 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-44020 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data